Russia and four other members of the Russian-led Collective Security Treaty Organization (CSTO) have begun joint military exercises in Belarus on Oct. 12, the organization said.
The drills will run from Oct. 12 until Oct. 16 at two training grounds on Belarusian territory, involving more than 1,500 military personnel, over 300 pieces of military equipment, and around 80 drones, according to the CSTO.
Military contingents from Belarus, Russia, Kazakhstan, Kyrgyzstan, and Tajikistan are participating in the exercises.
The drills focus on training CSTO "peacekeeping forces" and involve exercises to respond to biological threats, the organization said.
CSTO Deputy Secretary-General Mirlan Turgunbekov said in an Oct. 11 statement that the exercise is "particularly relevant given the escalating military and political situation."
The CSTO, which was established in 2002, includes Russia, Armenia, Belarus, Kazakhstan, Tajikistan, and Kyrgyzstan. Russia is by far the most powerful member of the alliance. Armenia is not particpating in the drills.
Belarus has supported Russia's full-scale war against Ukraine by allowing Moscow to use its territory as a staging ground for the full-scale invasion of Ukraine in 2022.
Although Belarus has not officially deployed its own troops to fight in Ukraine, Minsk has continued military cooperation with Moscow and provided support for Russia's war effort.
Ukrainian officials said on Sept. 14 that Russia is using Belarusian infrastructure, including LTE networks and repeater stations, to help maintain stable signals for Shahed-type drones during attacks on Ukraine.
Belarus held military exercises near its borders with Poland and Lithuania from Sept. 15 to 18, the Belarusian Defense Ministry said on Sept. 15.
Belarus has also been building new railway infrastructure in the country's southern Gomel Oblast that will be capable of receiving military trains carrying personnel and heavy equipment, the Belarusian Railway Workers' Community reported on Aug. 24.
In May 2026, Belarus and Russia held nuclear weapons exercises, amid Ukrainian concerns about deeper military cooperation between the two countries.